1. Field of the Invention
This invention relates to a surgical tool for simultaneously performing precision cutting and cauterizing of targeted tissues, and more specifically to a semiconductor knife constructed by appropriate semiconductor processing methods and techniques, said tool having electrocautery circuits imprinted thereon which are capable of heating at least a portion of the tool to sufficient temperatures to effect precise cauterization of adjacent targeted tissues.
2. Brief Description of the Prior Art
Presently, surgical devices for precision cutting are divided into different classes. Two important classes of such devices are microscalpels and laser scalpels. The former class has traditionally been solely a mechanical device, insofar as its only capacity was to physically separate tissues. This limited capacity, coupled with the unavoidable disruption of blood carrying members, required the use of another surgical tool for stemming the flow of fluids which might be initiated during the cutting. It has long been known that the sufficient application of heat to fluids, such as blood, or the tissue from whence such fluids flow, can cause their coagulation. Electrocautery instruments have been utilized in conjunction with mechanical scalpels to apply the heat necessary to cauterize the targeted tissues. These electrocautery tolos suffer from three substantial drawbacks. The first two of these are related to the surgical use.
First, separate electrocautery and mechanical scalpel devices often requires that the surgeon laboriously changes between using the scalpel and the electrocautery tool during the surgical procedure. Surgeons have found several manual means for overcoming this serious disadvantage, none of which truly reaches the ideal flexibility of the present invention. One such manual solutions is to have two surgeons working in the same surgical field, the first manipulating the cutting instrument, and the second manipulating the cauterizing instrument. For obvious reasons, including wasted expertise and the requirement of unnecessary coordinated activity, this solution is the least economically desirable, and is also the least efficient insofar as it often requires verbal communication between the two surgeons during periods of time when more critical information should be discussed.
A second solution which surgeons have discovered to attempt to overcome the serious drawbacks of separate scalpel and electrocautery instrumentation is to hold both instruments in the same hand, or at least in separate hands. Again, for obvious reasons, requiring a surgeon to hold both instruments in one hand, or at best having the two instruments in opposing hands, dramatically limits the flexibility of the surgeon's manipulative freedom.
The final, and least desirable manual methods of overcoming the drawbacks of separate instrumentation is to leave the tool which is not being utilized in the surgical field when it is not being actively used. Again, for obvious reasons, including impairing the visual field for the surgeon, it was known to be desirable to have a single tool which combines cauterizing and mechanical separation ability.
A substantial advance in the area of mechanical separation of tissues as well as cauterization was provided by the laser scalpel. Laser scapels utilize coherent light, often infrared light generated by a C02 or Yttrium-Aluminum-Garnet (YAG) power source, to ablate tissue away in a highly confined region. While the tremendous heat generated by the laser beam is more than substantial enough to cut through tissue as effectively as a scalpel (at least as efficiently as is necessary for many procedures) and also to cauterize surrounding tissues, the laser scalpel suffers from several important drawbacks as well.
Chief among these drawbacks is the fact that a laser scalpel which cuts by means of a coherent infrared beam is by definition invisible to the naked eye. Therefore, a surgeon must be able to manipulate the beam by watching the tissue surface which is literally burning before truly knowing the position of the "blade".
Second, but equally important is the inability to turn the cauterizing capacity off. More particularly, it is an important drawback of the laser scalpel that the cutting capacity is directly coupled to the heat generation, thus requiring at least some cauterization while cutting.
A related drawback of the laser scalpel, which is also a substantial drawback of present manual electrocautery instruments, is the imprecise nature of the cauterization. Both classes of surgical device cause substantial collateral damage to surrounding tissues. If cauterization is required near vital anatomical structures, great care must be taken to avoid damaging such tissues indirectly through the cauterization of the adjacent material. This problem is most severe in the field of microsurgery wherein many small vessels may be within a restricted field surgery, with only selected ones requiring cauterization.
In a sense, the cauterization instrument must combine the surgical precision of the microscalpel, the immediacy and strength of the laser, and also the selectivity of a separate instrument.
It is, therefore, a principle object of the present invention to provide a surgical instrument which combines precise tissue separation and cauterization ability within a single tool which enhances surgical flexibility.
It is further, an object of the present invention to provide a cauterizing cutting instrument which enhances visibility in the surgical field.
It is also an object of the present invention to provide a surgical instrument which permits greater precision in cauterization and cutting that instruments of the prior art.
It is an additional object of the present invention to provide an instrument which may be disposable, but which requires less wasted resources than present related surgical instruments.